Patent · US Expired

Power transfer apparatus for railroad track circuits

US4171788A · kind A · utility

1Cited by
3References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 8, 1978
Grant dateOct 23, 1979
Priority date
Expiry dateMay 8, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB61L1/20
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

At the remote end of a Type C track circuit, the conventional diode and the winding of a power transfer relay connected in multiple are connected across the rails over a transfer relay front contact. This transfer relay and the track relay at the near end are normally energized by the same half cycle of track current from the alternating current (AC) source. If the AC source fails, a track battery is connected across the rails at the remote end in series with the diode and transfer relay multiple network over a transfer relay back contact. The diode is so poled that the track relay is energized from the track battery with the same polarity as the rectified alternating current and does not release during the transfer operation. The diode bypasses substantially all track battery current away from the transfer relay. When the AC source is restored, the transfer relay is initially energized by the rectified alternating current through a low impedance capacitor, connected in multiple width the track battery and transfer relay back contact, and picks up to restore normal track circuit operation.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.